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A uniform circular track is the area bou...

A uniform circular track is the area bounded by two concentric circles. If the ares of the track is 1144 `m^(2)` and its width is 14 m, find the diameters of the two circles.

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To solve the problem of finding the diameters of two concentric circles that form a uniform circular track, we will follow these steps: ### Step 1: Understand the Problem We have a circular track formed by two concentric circles. The area of the track is given as 1144 m², and the width of the track is 14 m. We need to find the diameters of both circles. ### Step 2: Define Variables Let: - \( r \) = radius of the inner circle - \( R \) = radius of the outer circle Since the width of the track is 14 m, we can express the radius of the outer circle in terms of the inner circle's radius: \[ R = r + 14 \] ### Step 3: Area of the Track The area of the track is the difference between the area of the outer circle and the area of the inner circle: \[ \text{Area of the track} = \pi R^2 - \pi r^2 = 1144 \] Factoring out \(\pi\), we have: \[ \pi (R^2 - r^2) = 1144 \] ### Step 4: Substitute for R Substituting \( R = r + 14 \) into the area equation: \[ \pi ((r + 14)^2 - r^2) = 1144 \] ### Step 5: Expand the Equation Expanding \((r + 14)^2\): \[ (r + 14)^2 = r^2 + 28r + 196 \] Thus, we have: \[ \pi (r^2 + 28r + 196 - r^2) = 1144 \] This simplifies to: \[ \pi (28r + 196) = 1144 \] ### Step 6: Solve for r Dividing both sides by \(\pi\): \[ 28r + 196 = \frac{1144}{\pi} \] Using \(\pi \approx 3.14\): \[ 28r + 196 \approx \frac{1144}{3.14} \approx 364.24 \] Now, subtract 196 from both sides: \[ 28r \approx 364.24 - 196 \approx 168.24 \] Dividing by 28: \[ r \approx \frac{168.24}{28} \approx 6.01 \text{ m} \] For practical purposes, we can round \( r \) to 6 m. ### Step 7: Find R Now, we can find \( R \): \[ R = r + 14 = 6 + 14 = 20 \text{ m} \] ### Step 8: Calculate Diameters Finally, we calculate the diameters of both circles: - Diameter of the inner circle: \[ \text{Diameter}_{\text{inner}} = 2r = 2 \times 6 = 12 \text{ m} \] - Diameter of the outer circle: \[ \text{Diameter}_{\text{outer}} = 2R = 2 \times 20 = 40 \text{ m} \] ### Final Answer - Diameter of the inner circle: **12 m** - Diameter of the outer circle: **40 m** ---
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